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Gen 2 Wall Charger Now Only Goes to 16 Amps

RedNeB

Member
Jun 3, 2019
45
18
CT
I've had my Gen 2 wall connector for the last year+ with no issues. I've always got 48 amps of power and typically charge around 42-44 mph. Starting a couple of days ago the car only hits 16 amps and 12 mph when using it to charge. The light on the outside shows green like it's charging normally. No other errors of any sort. I'm on a 60 amp breaker and everything at the panel end looks fine (whole panel, breakers, etc. installed same day of the HPWC so everything pretty new). When I first connect the plug into the car it takes about a minute to ramp up and read the charge, which seems a lot longer than before. No issues charging at Superchargers and went to a local HPWC destination charger and had no issues there so everything points to an issue with the wall unit itself. I've tried the reset button a few times and have turned the breaker on/off to no avail. I've seen a few threads with a recent similar issue on Gen 3, but nothing like this on Gen 2. Of course, I'm a couple of months beyond the 1 year warranty. Anyone had an issue like this? I'm hoping the solution isn't buying another $500 charger.

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miimura

Well-Known Member
Aug 21, 2013
6,259
5,884
Los Altos, CA
On the display is says "16/48 A". That means that the Wall Connector is telling the car it can draw 48A. The car is only taking 16A. Have you tried increasing the amps manually on the screen? Does it start out higher and reduce by itself?
 
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RedNeB

Member
Jun 3, 2019
45
18
CT
On the display is says "16/48 A". That means that the Wall Connector is telling the car it can draw 48A. The car is only taking 16A. Have you tried increasing the amps manually on the screen? Does it start out higher and reduce by itself?

It starts out saying 1/48 A and then it slowly ramps up to 16/48 after a minute or so. Went to a local destination charger, which is the same type of wall connector and had no issues hitting 48/48 A. No issues at super chargers either. That leads me to believe it's not a car issue, but something wrong with either my wall charger or something in the breaker box. I have a basic voltage tester and it looks like I'm pushing 240V out of the wire so narrowing into the wall charger. Half of me says to bring over an electrician, but I think it will cost me $150 for them to just tell me everything in the panel looks fine and the box is the problem.
 

ucmndd

Well-Known Member
Mar 10, 2016
6,542
12,265
California
It starts out saying 1/48 A and then it slowly ramps up to 16/48 after a minute or so. Went to a local destination charger, which is the same type of wall connector and had no issues hitting 48/48 A.

The car remembers amperage settings based on geographic location, so driving to another location and trying another charger does not definitively implicate yours. Have you tried @miimura's suggestion and attempted to manually increase the amps on the car's charging screen? This is the first and most obvious troubleshooting step.
 
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CoachK

Member
May 5, 2019
21
12
Philadelphia
It starts out saying 1/48 A and then it slowly ramps up to 16/48 after a minute or so. Went to a local destination charger, which is the same type of wall connector and had no issues hitting 48/48 A. No issues at super chargers either. That leads me to believe it's not a car issue, but something wrong with either my wall charger or something in the breaker box. I have a basic voltage tester and it looks like I'm pushing 240V out of the wire so narrowing into the wall charger. Half of me says to bring over an electrician, but I think it will cost me $150 for them to just tell me everything in the panel looks fine and the box is the problem.


We have had the exact same issue. Have you tried your Mobile Connectors? Ours did not work in our home but did when we took them to a Tesla Service Center and plugged them into their 120V. So our thinking it might be an issue with the cars voltage sensitivity since this all started after updating to 2020.36.10 and only occurs at home where there tends to be more fluctuation vs commercial destination / Tesla Service.
 

RedNeB

Member
Jun 3, 2019
45
18
CT
The car remembers amperage settings based on geographic location, so driving to another location and trying another charger does not definitively implicate yours. Have you tried @miimura's suggestion and attempted to manually increase the amps on the car's charging screen? This is the first and most obvious troubleshooting step.

Yes, I tried manually adjusting the amps down on the settings. It didn't change anything. I'm occassionally getting the "Charge Rate Reduced - Unplug and Try Again" error. Sometimes I don't get that error. Very frustrating.
 

Sam1

Member
Sep 11, 2019
991
890
NV
Yes, I tried manually adjusting the amps down on the settings. It didn't change anything. I'm occassionally getting the "Charge Rate Reduced - Unplug and Try Again" error. Sometimes I don't get that error. Very frustrating.

There should be a reset button on the side of the wall charger, it's a little difficult to see. try hitting it.

Or cycle the breaker that powers the wall charger, that should do the same.
 

RedNeB

Member
Jun 3, 2019
45
18
CT
We have had the exact same issue. Have you tried your Mobile Connectors? Ours did not work in our home but did when we took them to a Tesla Service Center and plugged them into their 120V. So our thinking it might be an issue with the cars voltage sensitivity since this all started after updating to 2020.36.10 and only occurs at home where there tends to be more fluctuation vs commercial destination / Tesla Service.

After reading your post I did try the mobile connector and suprisingly had a similar issue. Very funny. I'm still on 2020.28.6. I have an update pending, but the wifi sucks in the garage so who knows when it will download. I'm hoping that might help with the issue. Very frustrating. How did you fix your issue or are you still dealing with it?
 

RedNeB

Member
Jun 3, 2019
45
18
CT
You need to try and adjust them UP, as in higher than 16 amps, while the car is charging at home on your wall connector. Does it allow you to set a higher number than 16?

View attachment 591558

I know exactly what you're referring to. It's already set at 48 amps by default. I've tried adjusting it down while charging and then raising it back up. I've also adjusted it down to 16 amps before plugging in the charger and then increasing it after I start charging. That's when it gives me the Unable to Charge error since it's set higher than what it's pulling. If you're referring to something else let me know.
 

brkaus

Well-Known Member
Jul 8, 2014
7,741
6,273
Austin, TX
Try unplugging and then see what it says? Can you increase to 48? And then plug in?

also, what does the voltage do? Does it start and stay close to 240?
 

RedNeB

Member
Jun 3, 2019
45
18
CT
Try unplugging and then see what it says? Can you increase to 48? And then plug in?

also, what does the voltage do? Does it start and stay close to 240?

I can increase to 48 without issue. It starts at 48 by default, but if I lower it down before or after charging I can raise it back up. If I move it under 16 amps and then try to raise it higher while charging I get the "Charge Rate Reduced, unplug and try again message". If I unplug it and try again the same thing happens as the original time I tried.

The voltage stays pretty much right around 238-240 volts. Not much fluctuation.
 

CoachK

Member
May 5, 2019
21
12
Philadelphia
After reading your post I did try the mobile connector and suprisingly had a similar issue. Very funny. I'm still on 2020.28.6. I have an update pending, but the wifi sucks in the garage so who knows when it will download. I'm hoping that might help with the issue. Very frustrating. How did you fix your issue or are you still dealing with it?

We are still dealing with it. We are trying to isolate where the issue lies. It can’t be the Wall Connector alone since the two mobile chargers we have are not working either but yet worked when we took them to Tesla Service (we assume that since they are in a Commercial site there power flow ( volts) are more steady. We had the house checked by an electrician and all the readings of power inflow (volts) coming in were 240+. The wall charger too showed 240 coming in. We manually increased the amp setting in the car while charging as a previous user posted. It’s set at 38amps and yet we are charging at 12-16 amp with 244 volts. In other threads someone seemed to think it might be caused by the software update and adjusting something with fluctuating volts making it more sensitive. We called someone we know at the local Tesla. They escalated and we shared that it seems to be happening to others based on the posts here.

It’s one of those circular conversations - Tesla says it’s the house, the electrician says its the car and the power company is MIA on our inquiry.
 

CoachK

Member
May 5, 2019
21
12
Philadelphia
We are still dealing with it. We are trying to isolate where the issue lies. It can’t be the Wall Connector alone since the two mobile chargers we have are not working either but yet worked when we took them to Tesla Service (we assume that since they are in a Commercial site there power flow ( volts) are more steady. We had the house checked by an electrician and all the readings of power inflow (volts) coming in were 240+. The wall charger too showed 240 coming in. We manually increased the amp setting in the car while charging as a previous user posted. It’s set at 38amps and yet we are charging at 12-16 amp with 244 volts. In other threads someone seemed to think it might be caused by the software update and adjusting something with fluctuating volts making it more sensitive. We called someone we know at the local Tesla. They escalated and we shared that it seems to be happening to others based on the posts here.

It’s one of those circular conversations - Tesla says it’s the house, the electrician says its the car and the power company is MIA on our inquiry.
We also went to our neighbors house and connected with our Mobile charger and had the same issue. So I don’t think it’s our house.
 

Quorky

Member
Oct 1, 2019
329
194
NYC
Just started having the same issue a few days ago. My setup is as follows:

NEMA 14-50
Getting 16 / 32amps (14mph vs the 28-30mph)

Tried unplugging, plugging in. Cycling the fuses. Voltmeter says 240ish volts as usual. Starts up fine, tries to accelerate above 16amps, get the "charging rate limited, unplug plug back in" error. Feels like it's not a coincidence that we just got a a larger incidence just recently (could be software related)... scheduled the appointment for next week. Let's see what they say.

PS. Funny thing is, after I set up the appointment a few days ago, the car started charging fine at 32/32amps, now went back to 16/32amps.
 

Cosmacelf

Well-Known Member
Mar 6, 2013
8,571
20,570
San Diego
Has anyone here tried:

1. Turn off the wall connector breaker
2. Making sure power is off (no light).
3. Taking cover of wall connector off.
4. Tighten down the screws for the incoming electrical wires.

The wall connector could very well be reading a loose connection. It has sophisticated software algorithms to detect that.
 
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mrElbe

Active Member
Aug 17, 2014
1,735
1,154
Stouffville, ON Canada
Since the problem also occurs using the Mobile connector then that eliminates the wall charger. Most likely an internal car charger error or as alluded earlier, software glitch. That charging works OK using another location wall charger is puzzling. Only explanation for that one is that your home circuit has suddenly developed wild voltage swings and the car uses the lowest setting it can handle safely.

Also if you have opened the wall charger as suggest above to tighten connections, check the correct setting of the Amperage switch. Flip it to another setting and back to correct one. This will clean the contacts.
 
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RedNeB

Member
Jun 3, 2019
45
18
CT
Has anyone here tried:

1. Turn off the wall connector breaker
2. Making sure power is off (no light).
3. Taking cover of wall connector off.
4. Tighten down the screws for the incoming electrical wires.

The wall connector could very well be reading a loose connection. It has sophisticated software algorithms to detect that.

Yep, I just did that this afternoon. Took apart my whole breaker panel to check the current coming out of the panel (no issues). Also tried turning off the breaker for 20 minutes. Tried a reset on the charger, as well. I even went as far as going out to Home Depot to buy the Torx 10 and 20 bits to open the charger up (electrician threw out the bits that came with it) because the ones I had didn't work with the security feature on Teslas. By the way, Telsa using Torx screws with the security feature is way overkill IMO. I took apart the charger and testing the power coming in - no issues. Tightened everything back up and still having the same issue.
 

RedNeB

Member
Jun 3, 2019
45
18
CT
Just started having the same issue a few days ago. My setup is as follows:

NEMA 14-50
Getting 16 / 32amps (14mph vs the 28-30mph)

Tried unplugging, plugging in. Cycling the fuses. Voltmeter says 240ish volts as usual. Starts up fine, tries to accelerate above 16amps, get the "charging rate limited, unplug plug back in" error. Feels like it's not a coincidence that we just got a a larger incidence just recently (could be software related)... scheduled the appointment for next week. Let's see what they say.

PS. Funny thing is, after I set up the appointment a few days ago, the car started charging fine at 32/32amps, now went back to 16/32amps.

Based on all the above it must be some kind of software issue. I'm installing the 2020.36.11 update right now to see if that does something. Otherwise, the only thing I can think of is that it's some kind of software issue. If I could get someone to plug their Tesla into my charger and have it work I could rule out the charger. But based on the fact that the same thing happened with the mobile charger, I'm pretty sure it's fine.
 

RedNeB

Member
Jun 3, 2019
45
18
CT
Since the problem also occurs using the Mobile connector then that eliminates the wall charger. Most likely an internal car charger error or as alluded earlier, software glitch. That charging works OK using another location wall charger is puzzling. Only explanation for that one is that your home circuit has suddenly developed wild voltage swings and the car uses the lowest setting it can handle safely.

Also if you have opened the wall charger as suggest above to tighten connections, check the correct setting of the Amperage switch. Flip it to another setting and back to correct one. This will clean the contacts.

Agreed. I think it's some kind of software compatibility issue. I don't think it has anything to do with power fluctuations. When I put in my charger a year ago I upgraded to 200 amp service, which required a completely new line in from the power line. The whole panel, breakers, etc. is brand new. Haven't had any power issues on any other appliances (have some sensitive home theater equipment that would probably have problems).

We'll see what happens when I install the update, but I don't think it's going to fix something. I believe another poster was having this issue on that software update.
 

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